Document the new "mark block" feature
tree2656fa9514f4bfd3253f704bb689be40100f7c2c
-rw-r--r-- 429 .gitignore
-rw-r--r-- 560 .gitmodules
-rw-r--r-- 224 .mailmap
-rw-r--r-- 255 .tgitconfig
drwxr-xr-x - Languages
-rw-r--r-- 2878 build.txt
drwxr-xr-x - contrib
drwxr-xr-x - doc
drwxr-xr-x - ext
-rw-r--r-- 1742 release.txt
drwxr-xr-x - src
drwxr-xr-x - test